unsorted stream intersection with grep, -xF magician

blewotah.sh

What is going on here is creating 2 streams with numbers from 1 to 100000 sorting randomly and finding with grep all lines that each of them contains. All of them, actually. -c flag is a shortcut for `| wc -l`, nothng more.

$> n=100000; time grep -f <(seq 1 $n | sort -R) <(seq 1 $n | sort -R) -c 
100000
grep -f <(seq 1 $n | sort -R) <(seq 1 $n | sort -R) -c  148.65s user 0.28s system 98% cpu 2:31.89 total


$> n=100000; time grep -xF -f <(seq 1 $n | sort -R) <(seq 1 $n | sort -R) -c 
100000
grep -xF -f <(seq 1 $n | sort -R) <(seq 1 $n | sort -R) -c  0.34s user 0.01s system 26% cpu 1.315 total

Hope it will never be useful for me =(